Adopt standard policy guidance and document provenance

docs/roadmap/implementation.md

@@ -1,6 +1,6 @@
 # Implementation Plan: Standard Repository Policy Alignment
 
-Status: Pending.
+Status: In progress.
 
 ## Scope and execution instructions
 
@@ -104,7 +104,14 @@ state checks before and after validation remain justified.
 
 ## Stage 1: Adopt common policy, provenance, and orientation
 
-Status: Pending.
+Status: Complete (2026-09-28).
+
+Verification: Compared all adopted policy text with the pinned Git objects;
+agents, testing, and meta match after template removal, metadata insertion, and
+whitespace cleanup. Reviewed the Narratio-specific documentation, architecture,
+and OSS deviations. The CC-BY-SA-4.0 text is byte-identical to the pinned
+source. `go test ./internal/doccheck` and `git diff --check` passed. Dependency
+attribution and release-policy/procedure alignment remain for later stages.
 
 Read the pinned adoption guide, all seven pinned policy templates, the attribution
 example for policies, and current local counterparts. Review the roadmap's local